The GOP chairmen of the House Oversight and Judiciary committees have asked the Department of Justice inspector general to investigate immediately whether classified information was mishandled at the department after the resignation of retired Lt. Gen. Michael Flynn as White House national security adviser.

In a Wednesday letter to DOJ Inspector General Michael Horowitz, Chairmen Jason Chaffetz, R-Utah, and Bob Goodlatte, R-Va., requested an "immediate investigation" into the possible mishandling of classified information, citing reports before Flynn's resignation about his discussions about sanctions with the Russian ambassador to the United States.

"We have serious concerns about the potential inadequate protection of classified information here," the Republicans wrote in the letter.

With the missive to the agency watchdog, top Republicans are taking President Donald Trump's lead.

Rep. Elijah Cummings has fired back, saying in a statement today, "Chairman Chaffetz appears to be taking his marching orders directly from President Trump's tweet yesterday - instead of investigating Gen. Flynn's lies to the vice president and the American people, as well as his troubling ties with Russia, the chairman chose to target those who brought them to light."

Cummings continued, "Congress should be doing independent oversight of the executive branch and protecting whistleblowers, not running interference while the White House conceals their abuses and misleads the American people for weeks. Chairman Chaffetz said he didn't want to go on 'fishing expeditions,' but that's exactly what he's doing here."

Since Flynn's resignation, the president has attacked the intelligence community for the leaks and blamed the media for Flynn's departure, though the White House has said Trump asked for Flynn's resignation.

"From intelligence, papers are being leaked, things are being leaked," Trump said at a White House news conference with Israeli Prime Minister Benjamin Netanyahu. "It's a criminal action, criminal act."

While Democrats have uniformly called for investigations into Flynn's conversations and the White House's handling of the episode, House GOP leaders have instead focused on the leaks.

House Intelligence Committee Chairman Devin Nunes, R-Calif., who is leading his panel's wide-ranging investigation into Russia and the election, plans to ask the FBI to assess leaks regarding Trump administration officials and classified information, an aide confirmed.

Nunes has downplayed concerns about Flynn's actions and whether to review them in committee, though several Senate Republicans want Flynn to testify before the Senate Intelligence Committee.